Selective switching



Nov. 16, 1943. E KLEINSCHMIDT 2,334,205

SELECTIVE SWITCHING Filed April 10, 1940 3 Sheets-Sheet l wiWmanATTORNEY5 Nov. 16, 1943. E. E. KLEINSCHMIDT 2,334,205

SELECTIVE SWITCHING Filed April 10, 1940 3 Sheets-Sheet 2 ATTORNEYS Nov.16, 1943. E, E. KLEINSCHMIDT 2,334,205

SELECTIVE SWITCHING Filed April 10, 1940 3 Sheets-Sheet 3 INVENTOR.

I Edward E. lziez'nsclzmidl Q W (1 Wm ATTORNEYS Patented 'Nov. 16, 1943UNITED STATES PATENT OFFICE SELECTIVE SWITCHING Edward E. Klcinschmidt,Highland Park, Ill.

Application April 10, 1940, Serial No. 328,958

22 Claims. (Cl. 177-353) This invention relates to improvements inselective switching systems and mechanisms, and more particularly toswitching arrangements for use in automatic telegraph, telephone, andsupervisory control systems.

In such systems, as for example in the Automatic telegraph switchingsystem disclosed in my application Serial No. 651.737. filed January 5,1933 and issued March 19, 1940, as Patent No. 2,193,967, the speed ofoperation and reliability of switching devices to establish the selectedtransmission line connection, is an important commercial factor. It isaccordingly a primary object of the present invention to provide noveland improved automatic switching mechanisms and improved switchingmethods that are more rapid and reliable in operation than the deviceshereto proposed for the performance of such operations.

While the devices and arrangements hereinafter disclosed are primarilydesigned to operate in the system disclosed in said Patent No.2,193,967, as will be apparent to those skilled in the art, it can, withsuch modifications in the circuit arrangements as are well known in theart applied thereto, be used in other types of automatic telegraphswitching systems, also in automatic telephone switching systems.

The commonly used automatic switching devices are step-by-step devicescontrolled by successive series of impulses which move a set ofconnecting brushes in two successive directions past rows of contactgroups arranged in a bank to the selected position. The number ofcontact groups that can be efliciently selected by a single selectorswitch in such prior art step-by-step mechanisms is comparativelylimited and the time of making each selection furthermore varies withthe number of stepping impulses required to step the selecting brushesto the selected position. A further object of my invention accordingly,is to provide improved switching mechanisms having a much larger numberof available efficiently selectable contacts or contact groups and inwhich the time of each selective movement is substantially uniform.

Other objects of the invention will appear from the detailed descriptionof the preferred embodiments hereinafter set forth, and from the termsof the appended claims.

The objects of my invention are accomplished by the use of improvedswitching mechanisms having stationary banks of contacts arranged in aseries of rows and a set or group of bodily movable contactors operatedby a permutation code selector mechanism under the control of twosuccessive groups of permutation code signals which act upon theselector and the switch mechanism connected thereto to position thegroup of bodily movable contacts to contact with any selected group ofcontacts in the stationary banks in accordance with nature of the twosuccessive groups of code signals received by the permutation codeselector.

In the drawings:

Figure 1 is a perspective view of a preferred form of switching in whichfor clarity of disclosure parts are broken away, only one corner of abowl-shaped support for the stationary banks of contacts is shown, andthe supporting framework is eliminated.

Figure 2 is a detailed fragmental view showing cam and clutch mechanismutilized in the device shown in Figure 1.

Figure 3 is a view more or less diagrammatic, and partially in sectionof the movable contact member of the device of Figure 1 in operatedposition, and of part of the operating mechanism therefor.

Figure 4 is a fragmental view showing the stop magnet of the device ofFigure 1 and its armature with the control contacts mounted thereon, anda cam unit all of which are shown in the operated position,corresponding to the operated position of the parts shown in Figure 3.

Figure 5 is a timing layout of the clutch control cams of the deviceshown in Figures 1, 2, 4, 8 and 9.

Figure 6 is a simple circuit diagram illustrating one form of system foroperating my improved switching mechanism.

Figure 7 shows a preferred form of distributor for transmittingpermutation code signals to operate my improved selective switch.

Figure 8 is a fragmental, more or less diagrammatic side elevation of amodified form of switching device embodying my invention in which themovable contact member has a vertical and rotary, instead of thespherical motion of the form of my invention shown in Figures 1 to 7.

Figure 9 is a more or less diagrammatic bottom view of the form ofinvention shown in Figure 8.

In the preferred embodiments of my invention I preferably utilize aselecting mechanism of the well known permutation code, single magnetprinting telegraph type having, a start-stop con trol shaft and aselector shaft, the selected position of which is determined by thereceived code combination of impulses. Various types of such telegraphselectors are well known, and in the drawings I have thereforeillustrated, and hereinafter will describe only so much of one form ofsuch well known mechanisms as will be necessary to make clear itsrelation to and co-operation with the further mechanism of the presentinvention. I have accordingly illustrated, and will briefly describe theselector mechanism fully disclosed in my application Serial No. 95,883,filed August 13, 1936, and issued March 5, 1940 as Patent No. 2,192,351,as the initial receiving mechanism'of the present invention.

Referring to Figure 1, start-stop shaft I is rotated through thefriction coupling 2 attached to gear 3 which in turn is constantlyrotated by a gear 4 mounted on shaft 5 of a motor not shown. Shaft I hasfixed to it a group of selector cams 8 which actuate pivoted selectorstop levers 8 under control of the armature 9 of magnet Stop levers 8control the progressive stopping of a stop wheel assembly I2 mounted onselector shaft I3 that is frictionally rotated through friction coupling4 fastened to gear I6 and shaft I3. Gear I6 is constantly driven fromgear 3 through a connecting idler gear I6. Stop lever I1 operated byarmature 9 releases shaft and selector cams 6 for rotation when a startimpulse is received on magnet I I. Latch frame I8 releases and locks thestop levers 8 in succession as they are operated under influence ofarmature 9 in response to received code combinations of signals,

and finally, through the action of cam I9 on lever 2 I, the last setstop lever 8 is released permitting stop wheel f2 and shaft |3 to assumethe start or normal position in which the normal stop lever 22 engagesthe normal stop 23, as shown in Figure 1. The foregoing selectormechanism and its operation is described in said Patent No. 2,192,351and as above pointed out, any one of a number of well known telegraphselecting mechanisms may be utilized in carrying out my invention nowabout to be described.

The normal rest position of my improved switch mechanism which isoperated by the startstop shaft I, and the selector shaft I3 is shown inFigure 1. On the left hand end of shaft I3 (Figures 1 and 2) is mounteda clutch assembly consisting of clutch members 24 and 25 that are keyedto, and slidably mounted on, shaft I3. Adjacent to each of the clutchmembers 24 and 25,

respectively, are gears 26 and 21 which are free i to revolve on shaftI3 but held in position relative to clutch members 24 and 25 by suitablecollars (not shown). Projecting lugs 28 on the clutch members 24 and 25co-act with projecting lugs 29 on hubs 3| of gears 26 and 21,respectively, to ensure engagement of the clutch members and gears whenthe respective clutches are actuated as hereinafter set forth.

Gear 26 is connected through an idler gear 32 to gear 33 fastened toshaft 34 (Figures 1 and 2). Gear 35 also fastened to shaft 34 mesheswith a spherical gear 36. Gear 36 is provided with projections 31 uponwhich movable switch member 38 is supported, and this assembly ispivoted in frame 39 on pivots 4I.

Gear 21 is connected through idler gear 42 to gear 43 fixed to shaft 44(Figures 1 and 2). Spiral gear 45 also fastened to shaft 44 is in meshwith a segmental spiral gear 46, which in turn is fastened throughsuitably journaled shaft 41. The end of shaft 41 is fastened at 48 to,and pivotally supports one side of frame 39 in which the movable contactcarrying member 38 is mounted. The opposite side of frame 39 ispivotally supported on spindle 49 suitably Journaled in the supportingframe work (Figure 3). The axis of pivotal movement of frame 39 aboutshaft 41 and spindle 49 is perpendicular to the axis of movement ofmember 38 about pivots 4|. Member 38 is, therefore, mounted foruniversal movement under the influence of gear 26 and gear 21. Springs56 connected to member 38 and segment gear 46 resiliently urge member 38to its normal position of rest shown in Figure 1,

Mounted on the end of shaft I is a gear 8| (Figures 1 and 4) whichrevolves in direction of the arrow and meshes with gear 52 in a two toone ratio. Gear 52 is fixed to shaft 53 on which the earns 54, 65 and 68(Figures 1, 2 and 4) and stop arm 51 are secured. One end of clutchlever 58 mounted on a pivot 59, engages the face of cam 64. A pin 68 onthe opposite end of lever 58 engages in agroove of, and operates clutchmember 24. One end of clutch lever 8| mounted on a pivot 62 engages theface of cam 68 and pin 6| on the opposite end of lever 62 engages in agroove of, and operates clutch member 26. Spring 63, the ends of whichare attached to clutch levers 58 and 6| holds the ends of the clutchlevers 58 and 6| against the faces of cams 54 and 56 respectively. Oneend of locking lever 64 mounted on a pivot engages the periphery of cam65, and the opposite end is provided with locking projection 66 adaptedto engage the teeth of lock wheel 61 under the influence of spring 66.

A band 69 is fastened to shaft 34 and carries a stop arm 69' which inthe normal or unoperated position rests against stop 1 I. Shaft 44carries stop arm 12 which in the normal or unoperated position restsagainst stop 13 under influence of springs 50.

Solenoid 14 (Figures 1 and 3) is mounted in the movable contact member38 and operates plunger 15. Attached to plunger 15 is rod 16 whichactuates block 11 (Figure 3) carrying insulated stud 18 (Figures 1 and3). Mounted on the outer end of rod 16 is an insulated block 19 to whichare fastened the switch contact springs 80 and 8|. The insulated stud 18operates contact springs 82, 83, 84 and 86 in a manner and for a purposethat will more fully hereinafter appear. Spring 81 (Figure 3) returnsrod 16 to its unoperated position when plunger 15 is released bysolenoid 14.

A bowl-shaped frame 81, more clearly shown in Figure 3, supports a bankof switch contact units 88 adapted to be selectably engaged by contacts8| and 82. The number of possible contact units in a row, as well as thenumber of rows of such contact units 88 depends on the number of stoppositions made available by the permutation code selector. The telegraphselector unit disclosed specifically is responsive to five-unitpermutation code combinations which provides for thirty-two selectivepositions of shaft 3. As hereinafter set forth, each selective operationof the switch is the result of two successive selecting codecombinations. Therefore, thirty-two rows of thirtytwo possible selectivepositions may be provided on frame 81, providing 1024 possible sets ofswitch contact assemblies 88.

Stop arm 51 (Figures 1 and 4) is controlled by a stop armature 89pivotally supported at 9| and retracted by spring 92. Armature 89 isattracted into the path of stop arm 51 by magnet 93 which is normallyenergized and when stoparm 51 engages armature 89, the position of thestop arm 51, with relation to clutch control earns 54 and 56 is shown inFigure 5 at the position of the letter A. In this position of the cams,cam 55 permits spring 68 to retain locking lever 64 in locked positionagainst lock wheel 61, and cam 56 permits spring 63 to retain clutchlever 6| in its operated position engaging clutch member 25 with gear21.

Contacts 94 and 95 mounted on an insulating block carried by armature 89are closed by the insulated pin 96 when stop arm 51 engages the stoparmature 89.

Operation of the switching mechanism No. 95,883. To operate the switchtwo successive groups of permutation code impulses each including astart impulse and a stop condition, are transmitted to selector magnetII. The start impulse releases shaft I and cams 5, in cooperation witharmature El, operate stop levers in accordance with the first receivedcode combination. Stop levers 5 act on stop wheel I2 to successivelystop shaft I3 in accordance with the positioning of stop levers 5 andfinally stop shaft I3 in its first selected position.

As shown in Figure 1, at the beginning of the cycle of operationsarmature 85 of magnet 53, which is normally energized, abuts the end ofarm 51, accordingly permitting rotation of shaft I without interference.

Immediately after the start of shaft I, cam 54 releases clutch lever 55which, under the influence of spring 53, shifts clutch member 24 intoengagement with gear 25. Gear 25 now revolves with shaft I3 and, throughidler gear 32 and gear 33 revolves shaft 34 and gear 35 turningspherical gear 35 and frame 38 about pivots 4| against the action ofspring 55 to a position corresponding to the first selected stopposition of stop wheel assembly I2.

Immediately after the first group of code signals is received on magnetII, shaft I will have turned gear 52 through gear 5| to a position wherecam 55 will release locking lever 54 to engage its projection 55 withlock wheel 51, thereby holding shaft 34 and, through the connected gear35 and spherical gear 35, the carrying frame member 35 in the firstselected position.

After receipt of the first group of permutation code signals by magnetII the normal stop impulse is received and shaft I is stopped. The camshaft 53 at this stage of operation will have turned through one halfrevolution, and will be stopped at the position indicated by "1st Sel."in Figure 5. Clutch member 24 is now disengaged from gear 25 and lockingprojection 55 of lever 54 is engaged with the teeth of lock wheel 51.Immediately thereafter a start impulse and a second group of permutationcode signals is received by magnet I I which again releases shaft I andshaft I3 as above described. Selector cams 5 and armature 9 will againcooperate in accordance with the code signals received to successivelystop the stop wheel assembly I2 at its final selected position and shaftI3 will be rotated to the same selected position.

When shaft I is again released on receipt of the second group ofpermutation code signals, gear 5I again revolves gear 52 and cam 55attached to gear 52, immediately releases clutch lever 5| which, underinfluence of spring 53 moves clutch member 25 into engagement with gear21. Gear 21 now turns with shaft I3 and, through idler gear 42, gear 43,shaft 44 and spiral gear 45, turns segmental spiral gear 45 a distancecorresponding to the selected positioning of shaft I3. Segmental spiralgear 45 turns the pivoted frame 35 through shaft 41,

and so turns movable contact frame member 35 and the connected sphericalgear 35 at right angles to the motion imparted to it by the gear 35through spherical gear 35. During this motion the teeth of gear 35 slidein the teeth of gear 35. Cams 54, 55 and 55 are now in the positionindicated in the timing layout, Figure 5, by A.

When the second set of code signals has been received, as hereinafterset forth in describing the operation of the system, magnet 93 beingenergized, as shown in Figure 4, armature 59 is positioned to engage arm51, and to stop rotation. This occurs before cam I5 acts on lever 2I torelease the last set stop lever 5, thus holding stop wheel assembly I2,shaft I3, and, through the connecting gears, movable contact frame 38'in the final selected position until the message transmission or othercontrol operation has been completed over the selected circuit. As stoparm 51 comes to rest against armature 59, contacts 94 and 95 are closedcompleting a circuit for solenoid I4 which then is actuated to engagecontacts 50 and 5I with the selected contact group 58, and to operatethe contacts 52 to 55 through stud 15, thus completing the selectedcircuit.

After the control operations have been completed, and the message istransmitted or directly after the control operations are completed, aswould be the case in a system where the message or talking circuits arejoined by auxiliary apparatus, the magnet 93 is momentarilyde-energized, armature 89 is released, and arm 51 is then freed so thatit can rotate to the normal position shown in Figure 1. When armature 59is released contacts 94 and 85 will be separated, tie-energizingsolenoid I4 and permitting spring 81 to disengage contacts and 8| fromthe selected contacts 55, and to restore contacts 52 to 85. Cam 55 willalso disengage projection 55 of lever 54 from wheel 51, and springs 55will then restore the parts to the normal position shown in Figure 1,with stop arms 59 and 12 engaging stops II and I3, respectively. ShaftI, upon being released by armature 55 assumes its normal stop positionand the last set stop lever 5 is released permitting stop lever 22 toengage normal stop 23.

Telegraph switching system The arrangement of contacts on the contactcarrying member 38 is adapted for a telegraph switching system, such forexample as is illustrated in Figure 6, comprising a station selectingcircuit, and a message transmitting circuit.

It is intended that a selective switch shall be made available to groupsof subscribers by connecting the station selector code transmittingapparatus and the message transmitting apparatus to the subscriberthrough line finders and circuits in the manner shown in my Patent No.2,193,967, or in the manner generally in use for telephone switchingsystems.

The signals for operating the selective switch originate in the box IIIImarked station selector code transmitting apparatus which is connectedin line I52, grounded at I03, and provided with a source of signallingcurrent I04. Selector magnet II of the switch is connected in line I02which is normally grounded through normally closed contact springs 84and 85 carried on switch contact member 38 and controlled by stud I5.Contact spring 85 is connected by conductor I05 to contact 55. When theselecv open at this time.

tive switch completes a connection in a small exchange having a singleselector the signal circuit is grounded through the selected subscriberscircuit. In large exchanges the circuit is carried through succeedingselector switches I86 through contacts 88, line I81 and ground at I88.

The message transmitting apparatus is located in the box I89 connectedin line III grounded at H2 and provided with a current supply source H3.Line III passes through slow acting relay H2, normally closed contactsprings 86 and 84 carried on member 38, through resistance H3 to groundH4. Contact spring 88 is connected by conductor H5 to contact 8|. Themessage circuit III is progressively'carried to ground H8 at eachsucceeding switch H1 through conductor H8 and H9 equal to that ofresistance H3 which is comparatively high. The purpose of thisarrangement being to keep the message circuit III closed until thecalling subscriber is connected to ground II 9 through the receivingperforator or called subscriber I2I, and also to control the automaticstarting of the message when the connection is finally completed. Thisis accomplished by providing a marginal relay (not shown) that operatesto start the transmitter when the high resistance H3 is cut out at thefinal receiving apparatus which occurs when the receiving apparatus isconnected and in operating condition, all as described in said PatentNo. 2,193,967.

Switch contacts 88, contact springs 88 and 8|, and contact springs 85and 86 are so arranged that insulated stud 18 will not open theconnections between ground contact 84 and contact springs 85 and 88until after the switch contact springs 88 and 8| are in contact with theselected switch contacts 88.

Magnet 93 is normally energized in the normal rest position of theselective switch through a circuit comprising ground I23, current supplyI24, armature I25 of slow relay H2, conductor I28 to ground I25. Stoparmature 88 of magnet 93 rests against the end of stop arm 51 (Figure 1)and insulated pin 96 is out of the path of the contact spring 94 so thatcontacts 94 and 95 are When however, the selective switch has been setto selected position as above described by two sets of permutation codeimpulses in succession, stop arm 51 will engage the end of armature 89and insulated pin 95 will close the contacts 94 and 95, closing acircuit from ground I21 battery I28 through conductor I29 to energizesolenoid 14 which thereupon operates plunger 15 and through rod 15 movesinsulated stud 18 to open the contact springs 85 and 88 and bringsswitch contact springs 88 and 8| into contact with the selected switchcontacts 88 completing the selected circuit so that transmission of themessage from transmitter I89 may proceed.

After a circuit connection is made and a message has been transmitted,the transmitter opens the message circuit a sufliclent time to releaseslow acting relay I2 which opens the circuit to magnet 93 releasing stoparmature 89 from stop arm 51 to permit shaft I to assume its normal stopposition. When this occurs contact springs 94 and 95 will open thecircuit I28 to thesolenoid 14, spring 81 will withdraw contacts 88 and8| from the switch contacts 88, and insulated stud 18 will permitcontact springs 85 and 85 tomturn to their positionagainst groundcontact 84. After the stop arm 51 is released cams 54, 55 and 58 as wellas stop arm 51 assume their normal stop position, as shown in Figure 1,thus releasing locking lever 84 from engagement with lock wheel 61.Clutch lever 8| is also moved by cam 58 to disengage clutch member 25from gear 21. The movable contact arm 38 is now disengaged from theoperating mechanism or the selecting switch and is returned to itsnormal position, as shown in Figure 1, by the springs 58.

Contacts 82 and 83 controlled by stud 18, which perform no function inthe operations hereinbefore described may be utilized for variouscontrol operations in switching systems to which the mechanism isadapted. It will also be understood by those skilled in the art thatprovision for busy indications and other functions will be made inswitching systems utilized in my improved switching mechanisms, such forexample as are made in my Patent No. 2,193,967.

Improved transmitting distributor The type of permutation code selectordescribed for operating the selective switch reaches its selectivepositions in selected steps of one half, one quarter, one eighth, onesixteenth, and one thirtysecond of a revolution, and movable contactmember 38 which is positioned directly by the selector mechanism willtherefore assume its ultimate selected position in corresponding steps,moving one half of its operating are under the control of the firstimpulse, one quarter during the next, and so on. To provide more timefor moving member 38 during the first selected positioning than wouldordinarily be available with transmission from a standard type oftransmitting distributor, I have provided a special type of transmittingdistributor (Figure 7). In this distrib utor ring I3I is connected toline I82, battery I84 and ground I83. The motor driven distributor armI32 through brushes I33 establishes contact successively betweensegments I34 to I4I. Contacts I34 to I38 are connected by conductors I42to the transmitter contacts I 43. Segment I39 is connected by means ofconductor I 44 to transmitter contact bar I 45 which in turn isconnected to line I82. The start-stop rotation of arm I32 is controlledby transmitter contacts I48 which are connected through battery I41 andconductor I48 to magnet I49. Armature I5I or magnet I49 normally holdsarm I32 from rotation. Contacts I48 are closed at the beginning of acode signal to energize magnet I49, freeing arm I 32 for a singlerevolution. As brushes I33 establish contact with segment I, line I82 isinterrupted transmitting a start condition. Thereafter as brushes I33establish contact successively with segments I34 to I38, line I82 ismade and broken depending upon the position of contacts I43 which areset in accordance with the code combination to be transmitted. Arm I 32then comes to rest on segment I39 closing line I82 to establish a stopcondition.

Segment I3 4 which controls the length of the first code impulse isabout twice as long as the succeeding segments I35 to I 38 to provide alonger interval for moving the comparatively heavy movable contactmember 38 over the first positioning of one half or its operating arc.

Modified switching mechanism Figures 8 and 9 show a modification inwhich the movable contact member 38 has a translatory motion for itsfirst positioning,- and a rotary motion for its second positioning. Theselector and control mechanism, illustrated in Figures. 1 to 5, is usedand similar parts bear the same reference numerals. In this modificationgear 26 controlled by clutch member 24 is bevel gear I56 that mesheswith a bevel gear II attached to suitably Journaled shaft I52 whichdrives gear I53, also attached to shaft I52. Gear I53 meshes with idlergear I53, which in turn meshes with a cylindrical rack I54 whichterminates in an extension rod I55. Rack I54 slides in a bearing I56 andthe rod I55 slides in a bearing I51. Movable contact member 38 isattached to the rod I55 at I58 and moves therewith. Gear 21 meshes withgear I58, driving shaft II, which drives gear I62 that in turn mesheswith pinion I63. Pinion I63 is mounted on and drives a shaft I64,Journaled at I65 in a suitable supporting frame work. Mounted on anddriven by shaft I64 is a cylindrical gear I88 which meshes with anddrives a segment gear I61. The opposite end of gear I61 is fastened toshaft I55 and the end of contact carrying member 38. A spiral spring I66fastened to shaft I64 at one end, and to pin In at its other end, holdsgears I86 and I61, and arm 38 in normal rotary position and gravity or asuitable spring holds the contact arm and rock assembly against stopabutment I12 in normal vertical or translatory position. Contacts 88 arecarried on a cylindrical segment frame I13 so positioned with respect toarm 38 and its contacts, that the connections are effected uponenergization of solenoid 14 after the arm has been selectivelypositioned.

In operation, as above set forth clutch 24 is actuated to cause rotationof gear 26 in accordance with the selected position assumed by shaft I3in response to the first received code combination. Rotation of gear 26,through gear I5I, I53 and I53 shifts rack I54 axially (vertically)- adistance determined by the first selected movement of shaft I3. Lockinglever 64 is then actuated to hold rack I54 in its selected translatoryor vertical position until the mechanism is restored. Contact arm 38 isthus positioned adjacent the selected row of contacts 88 on frame I13.

Clutch 25 is then actuated as above set forth in response to the secondreceived code combination to rotate gear 21 the distance selected by thesecond received code combination. This results in corresponding rotationof gears I62, I 66 and I61 to position arm 38 adjacent the selectedcontact group 88 in the previously selected contact row.

After the second selecting movement of arm 38 has been completed,armature 88 engages arm 51, the selector is locked in selected positionand solenoid 14 operates to engage contacts 86 and M with switch contact88. When the control operation has been completed magnet 93 ismomentarily de-energized, all as above set forth, to permit restorationof arm 38 under influence of gravity and spring I66 to normal positionshown in Figures 8 and 9.

The invention may be embodied in other speciiic forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1, In a selecting mechanism, a selecting memher having a normal positionand movable in two directions to a substantially equal number ofselectable positions in each direction; a first mechanism for movingsaid memberfrom said normal position in its first direction to any oneof a plurality of said selectable positions by a single movement of saidmember; means operable after the movement period for holding said memberat the end of said first movement; a second mechanism for moving saidmember from its position at the end of said first movement through itssecond direction to any one of a plurality of said available selectablepositions by a single movement of said member; means operable after saidsecond movement period for holding said member in the selected position;selector mechanism responsive to two successive received codecombinations of signals of equal length selectively controlling saidmechanisms and holding means; and means controlling the release of saidholding means to restore said member to its normal rest position.

2. The combination as set forth in claim 1 in which said last mentionedmeans comprises an electro-magnet and energizing means therefor.

3. The combination as set forth in claim 1 in which said last mentionedmeans comprises an electro-magnet, energizing means therefor, and a slowrelease relay in circuit with a permutation code message transmissioncircuit controlling said magnet,

4. In a selecting mechanism, a selecting member having a normal positionand movable in two series of successive steps of varying length to aselected position; mechanism for moving said member from said normalposition through its first series of steps; and operative to move saidmember from its position at the end of said first series of stepsthrough its second series of steps to the selected position; andselector mechanism responsive to successive received code combinationsof signals directly and selectively controlling said mechanisms.

5. Selective switching mechanism comprising a group of selectablecontacts arranged in rows; a member carrying contacts adapted to engagesaid selectable contacts and having a normal position; means carried bysaid member for engaging and disengaging said contacts; a first clutchcontrolled operating mechanism for moving said member from its normalposition to a position adjacent the selected row of contacts in saidgroup; means for holding said member adjacent said selected row ofcontacts; a second clutch controlled mechanism for positioning saidmember adjacent the selected contact in said selected row; means forholding said member adjacent the selected contact and for operating saidfirst mentioned means to engage said contacts; selector mechanismresponsive to successive received code combinations of signalsselectively controlling said clutch controlled operating mechanisms; andmeans controlling the disengagement of said contacts, the release ofholding means, and the restoration of said member to said normalposition.

6. In a selective switching system, switching mechanism selectivelyresponsive to permutations of selecting signalling conditions in aseries of steps of progressively decreasing length; and transmittingmeans for said permutations of conditions operative to prolong the firstselecting condition for each permutation with respect to the remainingselecting conditions thereof.

' 7. In a selective switching mechanism, a group of selectable contactmeans; a movable arm adapted to be selectively positioned with respect,

various positions under the control of said telegraph selector; -a firstand a second storing means; and means including control cams and a stopmagnet to store a first selected position of the shaft in said firststoring means, and to store a second selected position of said shaft insaid second storing means.

9. In a signalling system, receiving mechanism selectively responsive topermutations of selecting signalling conditions in a series of steps ofprogressively decreasing length; and transmitting means for saidpermutations of conditions operative to increase the operating time ofthe first step of the receiving mechanism by prolonging the firstselecting condition for each permutation with respect to the remainingselecting conditions thereof.

10. In a telegraph system, a permutation code transmitter operable totransmit code combinations of signalling conditions in which the firstsignalling condition is of greater length than the remaining signallingconditions; and a telegraph receiver responsive to said codecombinations in a series of steps of progressively decreasing length.

11. In a telegraph system, a permutation code transmitter operable totransmit code combinations of signalling conditions of progressivelydecreasing length in which the first signalling condition is ofsubstantially twice the length of the next succeeding signallingcondition; and a telegraph receiver responsive to said code combinationsin a series of steps of progressively decreasing length.

12. In a telegraph system, a permutation code transmitter operable totransmit code combinations of signalling impulses in which the firstimpulse of a code combination is of greater length than other impulsesin the combination; and a receiver including a switch operably connectedto said transmitter and movable in a series of steps of decreasinglength to a position determined by the code combination transmitted.

13. In combination, electromagnetic signal receiving means; a start-stopshaft operable by said receiving means in timed relation withpermutation code signals received by said means; a selector shaftoperable to be set in various selectable positions under control of saidreceiving means and successive operations of said startstop shaft; andmeans controlled jointly by said selector shaft and said start-stopshaft operable to store any pair of successive selectable positions ofsaid selector shaft responsive to said successive operations of saidstart-stop shaft.

14. A switching mechanism requiring two groups of permutation codesignals to complete a switching operation, comprising electromagneticsignal receiving means; a start-stop shaft operable by said receivingmeans in timed relation with permutation code signals received by saidmeans; selecting elements operable to be set in various positions inaccordance with the signals received by said means, under the control ofsaid receiving means and successive operations of said start-stop shaft;and means operable under the joint control of said start-stop shaft andsaid selecting elements to store any pair of selectable positions ofsaid selecting elements responsive to successive operations of saidstartstop shaft.

15. The combination as set forth in claim 13 together with contact meansoperable by said selecting elements to close switch circuits when bothselections are stored.

16. The combination as set forth in claim 13 together with meansoperable to lock the startstop shaft when the second group ofpermutation code signals have been received, and release means for saidlocking means.

17. A selector responsive to two successive permutation code signalscomprising a selector member movable in two directions to a selectedposition from a normal position; a selector shaft; means adjustable bysaid permutation code signals for positioning said shaft in accordancewith said signals; a mechanical connection between said shaft and saidselector member for adjusting said member in one of said directions inaccordance with the position of said shaft; another mechanicalconnection between said shaft and said selector member for adjustingsaid member in the other direction in accordance with the position ofsaid shaft; and means controlled by said successive permutation codesignals to render said mechanical connections successively eifective tocause the successive adjustments of said selector member.

18. Switching means responsive to two successive permutation codesignals; means for adjusting said switching means to a selectedposition; a selector member; means adjustable by said permutation codesignals for positioning said selector member in accordance with saidpermutation code signals; a mechanical connection between said selectormember and said adjusting means for adjusting the same in accordancewith one of said permutation code signals; another mechanical connectionbetween said selector member and said adjusting means for adjusting thesame in accordance with the other of said permutation code signals; andmeans controlled by said successive permutation code signals to rendersaid mechanical connections successively effective to cause successiveadjustments of said switching means to selected position.

19. The combination set forth in claim 18 in which said selector memberis a rotatable shaft which sets said switching means in selectedpositlon.

20. The combination as set forth in claim 18 in which said adjustablemeans comprises a selecting magnet and a start-stop shaft, and saidlast-mentioned means comprises clutch mechanism controlled by saidstart-stop shaft.

21. The combination as set forth in claim 18 in which said selectormember comprises a rotatable shaft; and said mechanical connections eachcomprises gearing driven by said rotatable shaft.

22. The combination as set forth in claim 18, together with means forlocking said adjustable means after receipt of the second of saidpermutation code signals, and means for releasing said locking means.

EDWARD E. KLEINSCHMIDT.

